http://crbug.com/510960#c5  relates, as part of Project Heaviside 	
http://j.mp/heaviside of which all stages except Stage 6/7 appear complete.

Update on Heaviside: Stage 6 is done. Stage 7 is done on animations side with this change:
https://codereview.chromium.org/1973083002
So now someone should redirect ElementId bindings from Layers to DisplayList items.

As for SPv2 animations, we already have a bug:
https://bugs.chromium.org/p/chromium/issues/detail?id=510960

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/d01445abcc37e8db7b6912815a3c9584a6762f93

commit d01445abcc37e8db7b6912815a3c9584a6762f93
Author: wkorman <wkorman@chromium.org>
Date: Fri Dec 16 00:54:30 2016

For SPv2, move updateAnimations() to follow scrolling and paint invalidation.

BUG= 666986 

Review-Url: https://codereview.chromium.org/2570723002
Cr-Commit-Position: refs/heads/master@{#438971}

[modify] https://crrev.com/d01445abcc37e8db7b6912815a3c9584a6762f93/third_party/WebKit/Source/core/frame/FrameView.cpp

 Issue 481262  has been merged into this issue.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/391cd0aa0d814f9f35bcd5a29df7ba91200e5d4f

commit 391cd0aa0d814f9f35bcd5a29df7ba91200e5d4f
Author: wkorman <wkorman@chromium.org>
Date: Wed Mar 15 09:25:33 2017

Enable more tests now passing under SPv2.

- stop skipping animations/ and transitions/ as most of those
  directories are now passing.
- five scroll-behavior tests that failed with
  --enable-threaded-compositing previously are now passing.
- perhaps unrelated to animation/scrolling specific work, but
  two compositing/ tests are now passing.

BUG= 666986 , 674317 
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Review-Url: https://codereview.chromium.org/2743373004
Cr-Commit-Position: refs/heads/master@{#457041}

[modify] https://crrev.com/391cd0aa0d814f9f35bcd5a29df7ba91200e5d4f/third_party/WebKit/LayoutTests/FlagExpectations/enable-slimming-paint-v2

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/dc3cab97b3a974ce7ae3d4372ea5af4b2bdd5621

commit dc3cab97b3a974ce7ae3d4372ea5af4b2bdd5621
Author: wkorman <wkorman@chromium.org>
Date: Thu Mar 16 19:26:29 2017

SPv2: Enable now-passing web-animations-api tests.

BUG= 666986 

Review-Url: https://codereview.chromium.org/2747083007
Cr-Commit-Position: refs/heads/master@{#457517}

[modify] https://crrev.com/dc3cab97b3a974ce7ae3d4372ea5af4b2bdd5621/third_party/WebKit/LayoutTests/FlagExpectations/enable-slimming-paint-v2

Duping this against another bug that's evolved to similarly track animation work remaining for SPv2, so we can have just one.

We already have  http://crbug.com/674655  for the touch event region work.